CFD Online Logo CFD Online URL
www.cfd-online.com
[Sponsors]
Home > Forums > General Forums > Main CFD Forum

integral length scale and cross-correlation (with openfoam data, LES pipe flow)

Register Blogs Members List Search Today's Posts Mark Forums Read

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old   June 4, 2010, 08:07
Default integral length scale and cross-correlation (with openfoam data, LES pipe flow)
  #1
jet
New Member
 
Join Date: Nov 2009
Posts: 12
Rep Power: 16
jet is on a distinguished road
Hi,
i want to calculate the integral length scale of a pipe flow in matlab.
the pipe flow (LES) is calculated with openfoam-1.6 .
I have read out the velocity components (cell center) of 1000 cells in a preview-folder at a one definite time-step.
Now I have to calculate the cross-correlation function (in x-direction):
1. step: i subtract the mean velocity from the axial-velocity-component in order
to obtain the fluctuating velocity u'

2. step: i calculate the cross-correlation as:

for i=1:1:1000;
ufluct(i)=uflukt(1)*uflukt(i)
end
ucross=ufluct./ufluct(1);
ufluct is the same as u' and ucross should be my cross-correlation coefficient?!
but my problem is, my code does not calculate the time-averaged cross-correlation-coefficient because i don't know wich kind of data i have to time-averaged.
i have read some books about it (Pope, Wilcox, Hinze and Lumley ...) but i can't implement their ideas in matlab.

it would be great if somebody has an idea or could explain me how to calculate the integral length scale correctly!
best regards,

jet
jet is offline   Reply With Quote

Old   November 7, 2016, 04:23
Default
  #2
New Member
 
Mr.liu
Join Date: Sep 2012
Posts: 27
Rep Power: 14
lx882211 is on a distinguished road
Hi, can you tell me how to calculate intergral scale, based on Openfoam data? Thank you very much.
lx882211 is offline   Reply With Quote

Reply

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are On
Refbacks are On



All times are GMT -4. The time now is 21:43.